Meet the researchers

Night-owl researcher

Doctoral candidate Maria Berdova has such great passion for her work that she does not always sleep at night.

Her enthusiasm is also contagious - especially when the object of Maria Berdova's research happens to be in the pocket of the person she is talking to.

‘Thin films are used everywhere nowadays – for instance, in the sensors of telephones and tablet computers. That is why we must know their characteristics: how strong and flexible they are. Thin films made by using atomic layer deposition, or ALD, work much better than traditional thin films. My work concentrates on testing the mechanical properties of ALD thin films,’ she explains.

Atomic layer deposition allows for precise and repeatable deposition both for even surfaces and three-dimensional objects. Microelectronics is the most important application of ALD thin films, but it is not the only one.

‘They are useful just about anywhere,’ Maria Berdova says.

‘On the inside surfaces of food packaging ALD thin films help improve the preservability of products. They are used in optical coatings for eyeglasses, for instance, to prevent unwanted reflections. They help solar panels absorb more solar radiation, thereby increasing their efficiency", she says.

Enthusiasm and cooperation

Maria Berdova wrote her master's thesis at the Petrozavodsk State University and Lappeenranta University of Technology. After graduating her choice of careers was easy.

‘Research work is my passion. It is wonderful to think that there are things that nobody else has done before, and that I get to be the first one to do so,’ she says enthusiastically.

Maria Berdova is working on her doctoral thesis in the Research Group for Microfabrication at the Department of Materials Science and Engineering. The group is headed by Professor Sami Franssila. Maria has only good things to say about him.

‘Sami Franssila has an amazing amount of experience and knowledge. He is also a supportive, inspiring and positive boss,’ she says.

Positive attitudes and tenacity are also required of a doctoral candidate.

‘The most difficult thing is to find a functioning theoretical model for the tests that I do. I might think about a solution day and night for up to a month. On the other hand, it is interesting - thinking helps me grow and develop as a researcher.’

Maria Berdova hopes that she can continue working with the same topic of research after she gets her doctorate. She feels that Aalto University is a magnificent working environment for a researcher.

‘It is easy to contact other departments and research groups here and to work with them, which is great,’ she says enthusiastically.

Accurate data using sensitive technology

'Getting into Tapani's group was a really big thing for me,' Xianming Kong says. He is one of the researchers in Professor Tapani Vuorinen's Wood Chemistry research group.

'In the group, I can continue working on spectroscopy, which I focused on in my doctoral dissertation, and use it to study a material of the future like biomass,' he says happily.

A non-invasive method

Spectroscopy is a method that analyses the radiation bouncing or scattering off the object being examined. Radiation consists of photons whose energy usually does not change during scattering. However, approximately one in ten million photons either emits energy or receives energy from a molecule it encounters. This results in inelastic scattering. The phenomenon is called Raman scattering, and each substance has specific Raman scattering properties. Therefore, Raman spectroscopy can be used to effectively identify molecules.

‘Since spectroscopy is an optical method where the material being studied remains untouched, an accurate analysis can be performed by Raman spectroscopy in almost any environment’, Xianming Kong explains.

‘My work focuses on surface-enhanced Raman scattering (SERS). In this method, Raman scattering is enhanced by placing the molecules being examined on a roughen noble metal surface. SERS has proved to be an efficient and sensitive analysis method even for examining single molecule.’

In addition to SERS, Xianming Kong's research interests include tip-enhanced Raman scattering (TERS). This method uses nanosized tips, usually made of gold or silver, to enhance Raman scattering.

‘I am currently learning how to prepare tips. My objective is to use TERS in the analysis of biomass in addition to other methods’, Xianming Kong says.

Collaboration and flexibility

The raw materials used in research are sometimes very mundane.

‘We use a fibre extracted from sawdust as the basis of our SERS substrates. The metal nanoparticles then assembly themselves on the surface of the fibre through the electrostatic effect’, Xianming Kong reveals.

‘The method is simple and inexpensive and it can be applied to the preparation of antibacterial surfaces in addition to SERS.’

Xianming Kong has a doctoral degree from Nanjing University, China. He began working in Tapani Vuorinen's research group in 2012 and he has thoroughly enjoyed his time at Aalto University.

‘The atmosphere of the department is pleasant: there is a lot of collaboration between research groups, the use of the laboratories is convenient and everyone helps one another. Having flexible working hours is also great,’ Xianming Kong says with gratitude.

University beats the business world

David Lloyd had said farewell to the academic world, but then ended up writing a doctoral dissertation and noticing that being a researcher does have its benefits.

David Lloyd did not plan on becoming a researcher, quite the contrary.

‘When I graduated from Delft University of Technology, I was eager to get a “real job” and I swore that I would never return to the academic world. As it happens, while I was working for a technology company, I noticed that a doctoral degree would open many doors’, Lloyd says.

In the end, the transition from the business world to the university world was quite painless.

‘There were many interesting opportunities available at Aalto University and to my delight I was offered a doctoral candidate's position in electrochemistry, which has always been my passion.’

Learning to take responsibility

In his doctoral dissertation, David Lloyd examined new battery chemistries and electrolytes for large-scale electricity storage. Lloyd thanks his supervising professor Kyösti Kontturi above all for having confidence in him.

‘He didn't interfere in small matters, such as how and when things should be done. He gave me a lot of ideas and suggestions, but I was responsible for making progress. At first it felt hard, but halfway through the project I realised how great it was that this was my project and I could decide which direction it was headed’, Lloyd describes and admits that sometimes sticking to the determined plan was difficult.

‘The research topic of a doctoral dissertation must be clearly outlined in order to be able to create a coherent piece of work and keep to the schedule. The funding model also required me to strictly keep to the topic. Sometimes I felt trapped in a cage with an enormous number of interesting research topics outside the cage.’

According to Lloyd, the best part of having finished the doctoral project is that he can now broaden his focus.

‘I now have a couple of years to concentrate on the ideas I had to forget during my doctoral dissertation. I'm also glad that I get to work with other people more often. A doctoral dissertation is quite an independent and even selfish project, but now I don't have to focus on being the main author of publications anymore. I can collaborate with several researchers and help as many doctoral candidates as possible’, Lloyd says enthusiastically.

”These are examples of self-assembling molecular materials, that is, materials that without external forces assemble to an ordered structure and have properties or functionality related to this self-assembling structure”, explains research group leader Maria Sammalkorpi. She leads a six person team Novel Materials via Self-Assembly which explores the characteristics of self-assembling molecular materials by computational and theoretical methods.

”Our main research tool is the computer, that is, we do not do experimental research. However, our collaboration groups do experimental research.” Maria Sammalkorpi tells.

Challenging and rewarding

Maria Sammalkorpi does applications oriented basic research. Applications can be found in many different fields.

”Self-assembling molecular materials can be used, for example, in self-healing coatings and solvation. Protein folding and the various structures formed by lipids are examples of self-assembly. Therefore studying self-assembling molecular materials helps understanding these biological systems. The formation and stability of polymer and lipid based drug transport capsules, and drug release from them, depend on self-assembly. Furthermore, with polymer films and membranes, molecular self-assembly phenomena influence for example the elasticity and mechanical strength of the films.” she lists.

According to Maria Sammalkorpi, the most challenging part of the work is the multiple scales in the phenomena. ”The essential phenomena for molecular self-assembly materials take place at the atomistic and molecular level, that is, at a very small length scale. We need to combine this microscopic level to the material properties at macroscopic scale.”

On the other hand, the reward of the research comes from the challenges.

”Basic research is often extremely slow. Most rewarding is to finally be able to solve the problem on which one has worked for a long time.” smiles Maria Sammalkorpi.

New environment teaches

Maria Sammalkorpi went to do post-doctoral research in the USA directly after her doctoral thesis defense. She recommends a change of environment to others as well.

”Doing research is similar everywhere but the way people work and how they look at things is different in different places, environments, and fields. Experiencing this teaches a lot.” she says.

Additionally, interdisciplinarity in research is almost self-evident to Maria Sammalkorpi and in her own research interdisciplinarity plays a major role.

”Our research topics are from chemistry but the methodology we use comes mainly from physics. Biotechnology and chemical engineering know-how are in significant part in our research, and the applications of the research fall under various industrial fields.” she summarizes.